Partlow Model 70 Gas Control

Taped for 3/4", 1 1/4", 2", or 3" pipe, and intended for use on horizontal pipelines, these valves are for temperature control on moderate to large capacity gas-fired appliances at higher pressure. Heavy-walled die-cast aluminum body. Internal mechanisms are machined brass, and aluminum and zinc die-cast parts. Designed for stationary applications only. Eleven operating ranges covering -30ºF to 1100ºF.

Quick Specifications

Taped for 3/4", 1 1/4", 2", or 3" pipe, and intended for use on horizontal pipelines, these valves are for temperature control on moderate to large capacity gas-fired appliances at higher pressure.

Partlow's series of self-operating, throttling gas valves have been specified for a wide variety of applications for more than 60 years. They maintain critical temperatures in gas-fired appliances without the characteristics sawtooth curves fo two-position controls.

Features a balanced double-ball valving mechanism. Pipe sizes 3/4", 1-1/4" and 2" for pressures up to 20 psi. Model 70 - 3", a special large capacity valve up to 5000 cfh operates at 1 psi instead of 20 psi. For very sensitive applications, the Model 713 was developed, with larger seat and ball dimensions. Model 70 series may be installed horizontally only.

Operation:

Adjustment is made by turning the setting knob, which advances or retracts a fixed level fulcrum in larger models, or raises or lowers the valve seat of smaller instruments. The plunger of the thermal element bears directly on the short leg of the lever or control valve.

There is no power requirement.

In the thermal element, expanding and contracting wiht deviations from appliance set point, advances and retracts the element plunger. The valve is thus throttled to decrease or increase the fuel suppy to the burners, restoring control temperature at the bulb.

The throttling action leads to a state of balance in which the valve is held at just that position which permits a gas flow sufficient to maintain control temperature under existing appliance load conditions. As load conditions change, a new valve position is sought and maintained as soon as equilibrium is established under the new condition.

An adjustable needle-type by-pass regulates the gas flow around the valve to supply minimum flame, if required.